Fluorine, periodic table F, is a gas at standard atmospheric pressure. It's most common isotope has 10 neutrons, for an atomic mass of 19.
Fluorine has been discovered on Mars by the Curiosity rover using its ChemCam scientific instrument. Some theories suggest that Fluorine and Chlorine are richer on Mars than on Earth (19.4 ppm on Earth, estimated 32 ppm on Mars). Stones which contain amphiboles and micas can contain 3% Fluorine by weight.
Uses of Fluorine
Fluorine is likely to be needed in massive quantities if people decide to terraform Mars. Most of the Super Greenhouse Gases which would have long lifetimes (when bombarded with ultraviolet light) are fluorine compounds. For example CF4, C2F6, SF6, NF3, CF3Cl, and others. Adding Super Greenhouse Gases to the atmosphere is an ideal way to warm the planet.
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